In computer systems, workstations and other electronics-intensive products and systems, ICs (integrated circuits) including processors, memory systems, controllers, logic circuits together with other system components and ASICs (application specific integrated circuits) are generally mounted on circuit boards within a system enclosure. The circuit boards are, in turn, generally coupled to connector terminals on a main system board (otherwise known as a motherboard or planar). The motherboard is typically reinforced and positioned adjacent to, and mechanically supported by, one of the two major walls or panels of an enclosure. The motherboard is typically the largest board in the enclosure, and in order to provide a stable support base for smaller circuit boards or so-called daughter boards, which may be inserted into connectors mounted on the motherboards, the motherboard is designed to have attached thereto a relatively thick and heavy plate so that the motherboard will not bend or lose position when a daughterboard is connected into or withdrawn from the motherboard connector terminal means.
High performance workstations and servers often employ a card-on-planar design. As the complexity of these systems increases, more integrated circuits and greatly increased pin count require more complicated connections to be made between the circuit boards and the motherboards to which the circuit boards are connected. The increasingly high pin count for board connectors require high insertion and extraction forces and yet require that planar flexure to be limited in order to ensure reliable connections. In addition, the planar itself must be protected from excessive flexure to prevent damage to solder joints, components, signal traces and vias.
Heretofore, when a circuit board was being installed into an enclosure, the main panel or wall of the enclosure needed to be removed in order to provide access to the connector on the motherboard and also to give an installer the leverage required to apply an in-line force to make certain a solid electrical connection is established and the daughterboard is securely connected. Even as systems are upgraded, and/or new functions or additional functions are implemented on new boards which need to be installed in existing systems and enclosures, or when boards need to be removed for troubleshooting or maintenance, a main panel or side of the electronics system enclosure typically needs to be fully removed.
In most system environments, space is critical. In systems or network environments or host-terminal systems, servers or computer enclosures are usually mounted in close quarters or even in cabinets or equipment racks where access is extremely limited. In such environments, board replacement or installation is a major task since the enclosure needs to be brought out to an open area and one of the main panels has to be removed in order to have access to the motherboard and connectors within the electronics enclosure. In some cases, the server unit may be mounted on a slidable tray support and the server may be slidably removed from its normal operating position, but even in that case, a major panel of the enclosure must be removed to gain access to the enclosed circuit boards to allow for the necessary leverage to install and remove the daughterboards from the planar board.
It is desirable, therefore, to provide a board-mounting method and structural apparatus in which boards may be more easily installed and removed from motherboards and/or other mountings within system enclosures without the need to remove one of the major panels from the enclosure, but still providing sufficient leverage to positively seat and unseat circuit boards mounted into system connectors on the motherboard. Accordingly, there is a need for an improved method and apparatus which is effective to enable inserting and extracting circuit boards into connection with system motherboards and multi-pin connectors therein. It is further desirable to provide a circuit board mounting and extracting system to facilitate circuit board connections to a motherboard without significant bending or flexing of the motherboard during circuit board insertion or extraction.